During light reaction of photosynthesis, the site for splitting of water molecule is:

During light reaction of photosynthesis, the site for splitting of water molecule is lumen side of grana thylakoid membrane. Splitting of water molecule is associated with PS-II of Z-scheme.The NADP reductase enzyme is located on the stroma side of the thylakoid membrane. The light independent reactions takes place in stroma matrix.Cristae of mitochondria is involved in respiration and not photosynthesis.